Shrink JS-allocated strings down to the correct size before passing them to Rust #3808
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khoover
reviewed
Jan 23, 2024
| @@ -1314,6 +1309,7 @@ impl<'a> Context<'a> { | |||
| const ret = encodeString(arg, view); | |||
| {debug_end} | |||
| offset += ret.written; | |||
| ptr = realloc(ptr, len, offset, 1) >>> 0; | |||
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Could add a check for whether len != offset before reallocing again, to avoid spurious allocs.
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I considered that, but I didn't think it'd be worth it since in the vast majority of cases the string won't take up the maximum amount of space anyway.
I'd be fine to add it if you want but I don't think the difference would be significant either way.
daxpedda
reviewed
Jan 23, 2024
…hem to Rust Fixes rustwasm#3801. I opted to solve it this way rather than just pass the capacity to Rust as well because it means the allocation isn't up to 3x bigger than it needs to be anymore. I also removed a TODO about fixing that.
Liamolucko
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Fixes #3801.
I opted to solve it this way rather than just pass the capacity to Rust as well because it means the allocation isn't up to 3x bigger than it needs to be anymore. I also removed a TODO about fixing that.